just how dangerous is the neutral wire?

electrocution is not much prevented with time delay (slow blow) fuses,

burnt motors and other rapid to slow discharge comenclature is protected by this devce though.

Something like that };-)

why am i still here ?

what's an RCD ? can somebody please spell it out ?

Residual Current Device, also known as an Earth Leakage Circuit Breaker. Safety trips which are designed to prevent serious injury or death by disconnecting the supply of electricity before the magnitude of current flowing through a person to earth reaches a level likely to cause injury or death. They are usually designed to operate at about

10mA. RCDs come in three forms: (a) plug adaptors which enable a 13A plug to be connected to a conventional socket, (b) plugs which are fitted directly to the cable connected to for example a hand tool, (c) circuit breakers operating on a number of 13A sockets and installed between the sockets and the electrical supply.

So, it does the same a GFCI does widely available in the Flat Lands of USA in a) GFI Extensions Cord b) GFI Receptacle c) GFI Breaker

Then watts the freakin problem with wiring down a receptacle in a bathroom from a Lighting Fixture box, that has only a (+-) 3 amp load on a 15 amp circuit that will only be adding a Hand Held Hair Blower or perhaps an additional 9 amps max

Correction: a Slow Blow may prevent electrocution, but it'll give you quite a Shock & Draw before blowing. so folk or regular household equipment may not survive the shock.

They are best kept away from residential applications being best for Commercial motorized equipment use where the initial equipment draw would trip from a redundant or closely rated circuit.

well while closing my panel in socks and thermals i touched the neutral bar confidently of course the floors are wooden here, but what if I had a static charge ? i'd probaly cause a draw on the Hot Buss, but I hope not on the neutral.

TGIF

Not unless you assume anything 'noticeable' is 'dangerous' ;-)

daestrom

I don't remember if it has already been posted in this long thread, but in the last half year or so GFCIs have presumably been changed so: - they will not work if wired backwards - with the supply wires connected to the "load" terminals (previously the outlet would not disconnect when the device was tripped - they will fail off (previously they failed to work they would often/always fail on)

what color are your thermals? i dont think red would be up to code :)

| In contact with the water is not the same as inside the human being. An | adult in good health would be safe from anything the neutral would | expose them to and a modern GFCI receptacle opens the neutral anyway.

What if the adult has heart and kidney problems?

Find me a GFCI NEMA 6-20R.

| Getting back to your hot tub breaker there may not be a neutral to the | hot tub but if there is it will only serve 120 volt pumps that have no | exposure to contact. In addition the controls on a listed hot tub are | mechanically operated not by direct electrical switching.

And if a leak develops in the pipe or hose to the pump, water leaks out, and engages the wiring?

| For six volts to be present on the neutral there has to be a high | resistance connection or other resistive fault on the neutral. For the | human being to make contact with that potential there has to be an | additional failure in the neutral, a code violation in the placement of | a receptacle, or an extension cord in use by a Darwin Award candidate.

You are assuming nothing breaks down. The code doesn't make such assumptions to the extent it can, and tries to make things be done to offer more than one means of protection. But in reality things do break down. You could have upwards of 120 volts on the neutral in some cases that were installed to code. It's because things can break.

|> | exposed you to contact. With the motor frames and all metallic |> | enclosures grounded via the Equipment Grounding Conductor (EGC) there |> | are three failures between you and a shock. Given the purpose of the US |> | NEC that is considered sufficient. |> |> Only 1 failure to reach a level hazardous to some people. |> | Describe it.

Open ground.

|> | The reason that GFCIs are used to protect spa users is that the voltage |> | drop on the EGC might well be over thirty volts under a fault condition |> | that involves an ungrounded conductor. The likelihood of that being |> | true for a neutral fault condition is far lower. |> |> No guarantee that a fault is going back to the EGC first. The person might |> be in series with that path. |> | Under what circumstances?

Person is grounded by another means.

|> | There is nothing stopping you from installing a three pole breaker with |> | a shunt trip coil and a ground fault detector to raise the level of |> | safety even higher. Alternatively you could use a contactor to energize |> | the circuit with the contactors coil current supplied via a ground fault |> | detection circuit. A three pole contactor would open all of the current |> | carrying conductors including the neutral. |> |> It would not be UL listed. |> | In that statement you are plain wrong. There are combinations of | contactor and ground fault detectors that are listed as type A GFCIs. | That is in fact the standard method for protecting the larger | commercial therapeutic hot tubs that are used in rehab centers and | hospitals.

I'm referring to what you suggested, that being to just take some parts and rig up your own GFCI system. That's what's not UL listed. But if you know of a GFCI protector that is listed (or a grouping of products that are listed as a group if put together a certain way), then show me.

GrayBlack with a tail,

but since i was returning from a switch party I grabbed the buss & volted before the inspector could demand another code requirement };-)

the gfci installation went well., I tested it before closing it up and the Test/Reset buttons DID work as JG & Charles mentioned, but this is my point, Neutral will not be the likely point of contact in a common Body to short circuit incident and I had doubts how much is normal function without the earth/ground applied.

on that note: Most Noticebly my GFCI Tester (again in this new test) Failed to make a trip without the Box ground reference, which brings up the full functional capacity of the gfci doubtful.

nevertheless it did trip by itself with the neutrals help alone., not from the external to trip source. I am not that worried about it anymore, of your knocking it in so vehemently and todays test };-)

=AEoy

Note on Topic: Neutral conductors may not dangerous, you could accidentaly touch them to other grounded metal surfaces by themselves and nothing, no harmful paths either, but the Potential is there if the circuits is a secondary node and it's returning form another branch circuit. so lets continue to be careful about it when such is present or suspect.

Today just as someone mentioned earier in the thread:

I got a 50 volt digital reading from a hot black lead and an isolated white return, this from a deadened branch off the same node and the box feeder: a Coffemaker was plugged to the unattached circuit wiring };-)

Live end -< 50vac dead end-< | coffemaker |

go figure ~> Analysis: perhaps the element loaded down the hot side and it gave me exactly 50volts on my fluke from the dead circuit leads to the hot feeder lead ;-o

any other views on this ?

Roy

here is the " be " that's missing between not and dangerous.,

i sound like such a spic at times };-)

How can you get 'upwards of 120 volts on the neutral' if the hot lead is opened by the GFCI? The original question was whether all GFCI's should open the hot *and* neutral, whereas some breaker-style GFCI's only open the 'hot'.

Unless you have a GFCI off of a sub-panel, and the sub-panel feeds other circuits, and the sub-panel to main panel neutral opens? On top of that the person has to come in contact with the neutral fed from the sub-panel even after the sub-panel's GFCI has opened the 'hot' to the hot-tub. How many simultaneous faults is this, three?

Granted, if we postulate enough things wrong/faults, anything can happen. But gee, should I start wearing a hard-hat to bed in case of meteor strikes?

daestrom

This sounds like your GFCI Tester is 'testing' the GFCI by connecting 'hot' to ground through a resistor (somewhat like one person suggested as a way to test one). And of course, while the EGC is open, no current will flow and the unit won't trip. But it *would still* trip if the you came in contact with the hot and provided a low enough resistance path back to the service panel ground that 5 ma could flow.

When using your tester and an open EGC, it's as if you grab the 'hot' while wearing insulated gloves, standing on an insulated mat. No current flow through your body, no imbalanced current, no danger, no trip.

daestrom

on that note: Most Noticebly my GFCI Tester (again in this new test) Failed to make a trip without the Box ground reference, which brings up the full functional capacity of the gfci doubtful.

-------------------------------------

It did not work with the external tester because of the way the external tester works. It connects a resistor from the "hot" to the ground pin. With only two wires attached, there is no connection to ground. This does not mean the GFCI will not work during a real fault. Think about this, if you throw a two wire appliance into a bathtub of water, the GFCI trips. The appliance was not connected to the ground pin on the receptacle. You are assuming that the ground current has to flow back on the grounding conductor in order for a GFCI to work. That is completely incorrect. It is meant to trip when there is a certain inbalance of current between the hot and neutral. The level was selected based on how much current is required to cause physical harm to humans. If you plug a cord with the insulation stripped from the energized conductor into an outlet and lay the energized conductor on a dry piece of wood, nothing happens. No trip. No current flow. If a person grabs the wire and is perfectly insulated, the GFCI does not trip. No current flow. Once the person touches something (like a water pipe, or wet concrete floor, etc) that allows enough current to flow, the GFCI will trip. No grounding conductor was required.

Charles Perry P.E.

Phils what ifs remind me of the material safety data sheet that was provided for the hand cleaner that was ordered for our fire house. The MSDS recommended that users ware eye protection, a protective apron, and; wait for it; gloves while using the product.

-- Tom H

Ah yes, one of my pet peeves with digital meters. Of course one of my other pet peeves is having someone believe, and use, a measurement without understanding how that measurement is actually made by the instrument. This example fits both I suspect.

Charles Perry P.E.